Allocating port numbers

We can control the local port addresses used when making outgoing connections. For example, if your firewall allows only certain ranges of port numbers, we can use MQIPT to ensure that output originates from a valid port.

Before starting

Before you start to use this scenario, make sure that we have completed the prerequisite tasks listed in Getting started with IBM MQ Internet Pass-Thru.
Install MQIPT on a multihomed computer.

Figure 1. Port allocation network diagram

This diagram shows the connection from a IBM MQ client (client1.company1.com on port 1415) through MQIPT to a IBM MQ server (server1.company2.com on port 1414).

Procedure

To allocate port numbers, complete the following steps:

Set up MQIPT. Edit mqipt.conf and add the following route definition:

[route]
ListenerPort=1415
Destination=server1.company2.com
DestinationPort=1414
LocalAddress=10.10.6.7
OutgoingPort=2000
MaxConnectionThreads=20

Start MQIPT. Open a command prompt on the IBM MQ system, and enter the following command:

C:\mqipt\bin\mqipt C:\mqiptHome -n ipt1

where C:\mqiptHome indicates the location of the MQIPT configuration file, mqipt.conf, and ipt1 is the name to be given to the instance of MQIPT. The following messages indicate that MQIPT has started successfully:

5724-H72 (C) Copyright IBM Corp. 2000, 2020 All Rights Reserved
MQCPI001 IBM MQ Internet Pass-Thru V9.2.0.0 starting
MQCPI004 Reading configuration information from mqipt.conf
MQCPI152 MQIPT name is ipt1
MQCPI021 Password checking has been enabled on the command port
MQCPI011 The path C:\mqiptHome\logs will be used to store the log files
MQCPI006 Route 1415 is starting and will forward messages to :
MQCPI034 ....server1.company2.com(1414)
MQCPI035 ....using MQ protocol
MQCPI069 ....binding to local address 10.10.6.7 when making new connections
MQCPI070 ....using local port address range 2000-2019 when making new connections
MQCPI078 Route 1415 ready for connection requests

At a command prompt on the IBM MQ client system, enter the following commands:
1. Set the MQSERVER environment variable:
```
SET MQSERVER=MQIPT.CONN.CHANNEL/tcp/10.7.20.5(1415)
```
2. Put a message:
```
amqsputc MQIPT.LOCAL.QUEUE MQIPT.QM1
Hello world
```
  Press Enter twice after typing the message string.
3. Get the message:
```
amqsgetc MQIPT.LOCAL.QUEUE MQIPT.QM1
```
  The message, "Hello world" is returned.

Parent topic: Getting started with IBM MQ Internet Pass-Thru